Everolimus-induced epithelial to mesenchymal transition (EMT) in bronchial/pulmonary cells: when the dosage does matter in transplantation.

BACKGROUND: Everolimus (EVE) is a mammalian target of rapamycin inhibitor (mTOR-I) widely used in transplantation that may determine some severe adverse events, including pulmonary fibrosis. The pathogenic mechanism of mTOR-I-associated pulmonary toxicity is still unclear, but epithelial to mesenchymal transition (EMT) of bronchial/pulmonary cells may play a role. METHODS: Three cell lines-human type II pneumocyte-derived A549, normal bronchial epithelial, and bronchial epithelial homozygous for the delta F508 cystic fibrosis-causing mutation-were treated with EVE or tacrolimus at different concentrations. Real-time polymerase chain reaction and immunofluorescence were used to evaluate mRNA and protein levels of EMT markers (alpha-SMA, vimentin, fibronectin). Subsequently, in 13 EVE- and 13 tacrolimus-treated patients we compared the rate of lung fibrosis, estimated by an arbitrary pulmonary fibrosis index score (PFIS). RESULTS: Biomolecular experiments demonstrated that high doses of EVE (100 nM) up-regulated EMT markers in all cell lines at both gene- and protein level. High concentrations of EVE were also able to reduce the mRNA levels of epithelial markers (E-cadherin and ZO-1) and to induce the phosphorylation of AKT. In the in vivo part of the study, PFIS was significantly higher in the EVE-group than the tacrolimus-group (p = 0.03) and correlated with trough levels (R2 = 0.35). CONCLUSIONS: Our data reveal, for the first time, a dose-dependent EVE-induced EMT in airway cells. They suggest that clinicians should employ, wherever possible, low dosages of mTOR-Is in transplant recipients, assessing periodically their pulmonary function.

Safety and Diagnostic Yield of Transbronchial Lung Cryobiopsy in Diffuse Parenchymal Lung Diseases: A Comparative Study versus Video-Assisted Thoracoscopic Lung Biopsy and a Systematic Review of the Literature.

BACKGROUND: A diagnosis of interstitial lung diseases (ILDs) may include surgical lung biopsy (SLB), which is associated with significant morbidity and mortality and also appreciable costs. Transbronchial lung cryobiopsy (TBLC) is adopting an important role. OBJECTIVES: The aim of this study was to compare the diagnostic yield (DY) and safety of TBLC and SLB in a large cohort of patients and to perform a systematic review of the literature as well as a meta-analysis. METHODS: We performed a retrospective analysis of 447 cases with ILD undergoing TBLC and/or SLB and a systematic review of the literature (MEDLINE and Embase for all original articles on the DY and safety of TBLC in ILDs up to July 2015). RESULTS: A total of 150 patients underwent SLB and 297 underwent TBLC. The median time of hospitalization was 6.1 days (SLB) and 2.6 days (TBLC; p < 0.0001). Mortality due to adverse events was observed for 2.7% (SLB) and 0.3% (TBLC) of the patients. Pneumothorax was the most common complication after TBLC (20.2%). No severe bleeding was observed. TBLC was diagnostic for 246 patients (82.8%), SLB for 148 patients (98.7%, p = 0.013). A meta-analysis of 15 investigations including 781 patients revealed an overall DY of 0.81 (0.75-0.87); the overall pooled probability of developing a pneumothorax, as retrieved from 15 studies including 994 patients, was 0.06 (95% CI 0.02-0.11). CONCLUSION: Cryobiopsy is safe and has lower complication and mortality rates compared to SLB. TBLC might, therefore, be considered the first diagnostic approach for obtaining tissue in ILDs, reserving the surgical approach for cases in which TBLC is not diagnostic.

Echocardiographic findings and plasma endothelin-1 levels in obese patients with and without obstructive sleep apnea.

OBJECTIVE: Obstructive sleep apnea (OSA) and obesity are increasingly prevalent worldwide. Both promote endothelial dysfunction contributing to systemic and pulmonary hypertension over time. Endothelin-1 (ET-1) plays a pivotal role in the development of pulmonary hypertension (PH). The aim of the present study was to assess the association between plasma ET-1 and echocardiographic findings in obese individuals with and without OSA, as well as in non-obese patients with OSA. METHODS: Ninety-seven subjects (56 males) were enrolled in the study. All subjects underwent the following tests: venous endothelin-1 levels, pulmonary function testing, and arterial blood gas analysis. All patients except controls underwent transthoracic echocardiography and portable testing for sleep-disordered breathing. RESULTS: Plasma ET-1 levels were significantly higher in obese patients, both with and without OSA (respectively, n = 30 (mean value, 268.06 ± 49.56 pg/ml) and n = 32 (mean value, 263.12 ± 65.26 pg/ml)), compared with non-obese patients with OSA or to healthy controls (respectively, n = 20 (mean value, 149.8 ± 23.09 pg/ml) and n = 15 (mean value, 152.3 ± 27.64 pg/ml); p < 0.0001). Pulmonary artery pressure (PAPs) in obese patients with OSA were significantly higher than in obese patients without OSA (p < 0.0001), while there was no statistical difference between PAPs of obese patients without OSA, compared with the group of non-obese OSA patients. Plasma ET-1 levels significantly correlated with systolic PAPs in obese patients both with and without OSA (respectively, n = 30, r = 0.385, p = 0.03567; n = 32, r = 0.3497, p = 0.0497). CONCLUSIONS: Our study suggests that endothelin levels are more strongly associated with weight than the presence of sleep-disordered breathing, but pulmonary artery hypertension is associated with both weight and OSA.

Correlation between inflammatory markers of atherosclerosis and carotid intima-media thickness in Obstructive Sleep Apnea.

Obstructive Sleep Apnea (OSA) is a sleep-related breathing disorder associated with the development of cardiovascular diseases and atherosclerosis. Systemic inflammation plays an important role in the development of cardiovascular complications in OSA patients. The aim of the study was to evaluate the relationship between carotid intima-media thickness (cIMT) and inflammatory markers plasma levels in OSA patients. We enrolled 80 OSA patients and 40 controls matched for age and body mass index (BMI). The presence and severity of sleep apnea was determined by in-laboratory portable monitoring (PM). Demographic data, blood pressure, heart rate, and cIMT were measured. High-sensitive C-Reactive Protein (hsCRP), interleukin (IL)-6, tumor necrosis factor (TNF)-α and pentraxin (PTX)-3 serum concentrations were detected. cIMT was higher in OSA patients than controls (0.89 ± 0.13 mm vs. 0.65 ± 0.1 mm, p < 0.01). Moderate-severe OSA patients (0.95 ± 0.09 mm) had significantly increased cIMT than mild OSA (0.76 ± 0.1 mm; p < 0.01) and control (0.65 ± 0.1 mm; p < 0.01). hsCRP, IL-6, TNF-α, and PTX-3 in patients with OSA (1.67 ± 0.66 mg/L, 2.86 ± 1.39 pg/mL, 20.09 ± 5.39 pg/mL, 2.1 ± 0.59 ng/mL, respectively) were significantly higher than in controls (1.08 ± 0.53 mg/L, p < 0.01; 1.5 ± 0.67 pg/mL, p < 0.01; 12.53 ± 3.48 pg/mL, p < 0.01; 1.45 ± 0.41 ng/mL, p < 0.01, respectively). Carotid IMT was significantly correlated to CRP (r = 0.44; p < 0.01), IL-6 (r = 0.42; p < 0.01), TNF-α (r = 0.53; p < 0.01), and PTX-3 (r = 0.49; p < 0.01). OSA patients showed increased cIMT, CRP, IL-6, TNF-α, and PTX-3 levels. Inflammatory markers levels are correlated to cIMT in OSA patients.

Home unattended portable monitoring and automatic CPAP titration in patients with high risk for moderate to severe obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea is a disorder characterized by recurrent obstruction of the upper airways during sleep. The high prevalence of this disease led to proposed new strategies based on the home evaluation and management of patients. OBJECTIVE: To compare home unattended portable monitoring and automatic CPAP titration with attended in-laboratory analysis, in a sample of patients with high risk for moderate to severe obstructive sleep apnea. METHODS: We enrolled 131 subjects, who were randomly divided into 2 groups: the home group (n = 66) was diagnosed and titrated at home; the laboratory group (n = 65) was analyzed in the sleep laboratory of our hospital. Diagnostic evaluations were carried out with portable monitoring at home, and with polysomnography in the sleep laboratory. Titration of CPAP was performed with the same automatic CPAP device in both groups. RESULTS: At the end of the study, 13 (19%) subjects had dropped out of the home group, and 9 (14%) of the laboratory group (P = .50). There were no significant differences among groups in both baseline and with-CPAP values of apnea-hypopnea index, oxygen desaturation index, and total sleep time with SpO2 below 90%. In the home group, the therapeutic pressure values reached at the end of each unattended home titration night were similar. CONCLUSIONS: A home diagnosis and titration approach should be considered in a subset of patients with obstructive sleep apnea. A single unattended titration night is sufficient to determine the therapeutic pressure.